Field of invention
This invention relates to a motor-type damper unit using a motor for opening/closing an opened/closed member such as a baffle with respect to an opening portion.
Hitherto, for example, a motor unit having a motor such as an AC synchronous motor or a stepping motor as a drive source as shown in FIG. 17 has been known as a motor-type damper unit. (Refer to JP-A-6-109354.)
In FIG. 17, a motor-type damper unit 100 comprises a baffle 102 and a drive mechanism section 103 such as an AC synchronous motor placed with a rotation fulcrum shaft 101 between.
The motor-type damper unit 100 in the related art converts the rotation torque of the synchronous motor into the thrust direction torque of a spindle. The thrust direction torque of the spindle causes the baffle 102 to rotate on the rotation fulcrum shaft 101. Thus, the rotation direction torque is converted into the thrust direction torque for opening/closing the baffle 102.
The described motor-type damper unit 100 is used with a refrigerator 110 for controlling taking cold air into the refrigerator in a manner as shown in FIG. 18. That is, the refrigerator 110 is separated into a freezer 111, a cold room 112, and a vegetable room 113, the freezer 111 being provided with an evaporator 114 on the bottom. A fan motor 115 is disposed in the rear of the evaporator 114 for sending and circulating provided cold air to and through the freezer 111 and the cold room 112. A compressor 119 for liquefying a cooling medium is placed in a lower part of the refrigerator 110.
A partition plate 116 is placed between the evaporator 114 and the freezer 112 for shutting off a direct flow of cold air provided by the evaporator 114 into the cold room 112. On the other hand, a cold air circulation passage 117 is formed between the rear of the partition plate 116 and the rear inner wall of the refrigerator 110, and the motor-type damper unit 100 is disposed in the cold air circulation passage 117. When the baffle 102 of the motor-type damper unit 100 is opened, the cold air circulation passage 117 for allowing cold air to flow enters a crank state. The motor-type damper unit 100 is installed in such a manner that it is held on a partition wall 118 forming a part of the cold air circulation passage 117.
The motor-type damper unit 100 in the related art is of the type wherein it is orthogonal to the cold air circulation passage 117 as described above, and only the damper unit for bending the cold air flow at right angles can be used. Moreover, since the cold air circulation passage 117 becomes like a crank, a protuberance width of the partition wall 118 to the inside of the refrigerator 110, M, grows as shown in FIG. 18, causing the volume of the refrigerator 110 to be decreased.
Further, the baffle 102 is not opened to a position at which it becomes parallel to the cold air flow, and is opened only to a slanting position as shown in FIG. 18, thus the baffle 102 becomes resistant to the cold air flow; it is not preferred for rapid diffusion of the cold air. For the motor-type damper unit 100 itself, a width of the drive mechanism section 103, N, grows; the portion of the drive mechanism section 103 becomes a large dead space.
It is therefore an object of the invention to provide a motor-type damper unit using a one-way drive motor capable of rotating an opened/closed member such as a baffle in an open/closing direction.